4 * This is the central lockd service.
6 * FIXME: Separate the lockd NFS server functionality from the lockd NFS
7 * client functionality. Oh why didn't Sun create two separate
8 * services in the first place?
10 * Authors: Olaf Kirch (okir@monad.swb.de)
12 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
15 #include <linux/module.h>
16 #include <linux/init.h>
17 #include <linux/sysctl.h>
18 #include <linux/moduleparam.h>
20 #include <linux/sched.h>
21 #include <linux/errno.h>
23 #include <linux/uio.h>
24 #include <linux/slab.h>
25 #include <linux/smp.h>
26 #include <linux/smp_lock.h>
27 #include <linux/mutex.h>
28 #include <linux/kthread.h>
29 #include <linux/freezer.h>
31 #include <linux/sunrpc/types.h>
32 #include <linux/sunrpc/stats.h>
33 #include <linux/sunrpc/clnt.h>
34 #include <linux/sunrpc/svc.h>
35 #include <linux/sunrpc/svcsock.h>
37 #include <linux/lockd/lockd.h>
38 #include <linux/nfs.h>
40 #define NLMDBG_FACILITY NLMDBG_SVC
41 #define LOCKD_BUFSIZE (1024 + NLMSVC_XDRSIZE)
42 #define ALLOWED_SIGS (sigmask(SIGKILL))
44 static struct svc_program nlmsvc_program;
46 struct nlmsvc_binding * nlmsvc_ops;
47 EXPORT_SYMBOL_GPL(nlmsvc_ops);
49 static DEFINE_MUTEX(nlmsvc_mutex);
50 static unsigned int nlmsvc_users;
51 static struct task_struct *nlmsvc_task;
52 static struct svc_rqst *nlmsvc_rqst;
53 unsigned long nlmsvc_timeout;
56 * These can be set at insmod time (useful for NFS as root filesystem),
57 * and also changed through the sysctl interface. -- Jamie Lokier, Aug 2003
59 static unsigned long nlm_grace_period;
60 static unsigned long nlm_timeout = LOCKD_DFLT_TIMEO;
61 static int nlm_udpport, nlm_tcpport;
63 /* RLIM_NOFILE defaults to 1024. That seems like a reasonable default here. */
64 static unsigned int nlm_max_connections = 1024;
67 * Constants needed for the sysctl interface.
69 static const unsigned long nlm_grace_period_min = 0;
70 static const unsigned long nlm_grace_period_max = 240;
71 static const unsigned long nlm_timeout_min = 3;
72 static const unsigned long nlm_timeout_max = 20;
73 static const int nlm_port_min = 0, nlm_port_max = 65535;
76 static struct ctl_table_header * nlm_sysctl_table;
79 static unsigned long get_lockd_grace_period(void)
81 /* Note: nlm_timeout should always be nonzero */
83 return roundup(nlm_grace_period, nlm_timeout) * HZ;
85 return nlm_timeout * 5 * HZ;
88 static struct lock_manager lockd_manager = {
91 static void grace_ender(struct work_struct *not_used)
93 locks_end_grace(&lockd_manager);
96 static DECLARE_DELAYED_WORK(grace_period_end, grace_ender);
98 static void set_grace_period(void)
100 unsigned long grace_period = get_lockd_grace_period();
102 locks_start_grace(&lockd_manager);
103 cancel_delayed_work_sync(&grace_period_end);
104 schedule_delayed_work(&grace_period_end, grace_period);
107 static void restart_grace(void)
110 cancel_delayed_work_sync(&grace_period_end);
111 locks_end_grace(&lockd_manager);
112 nlmsvc_invalidate_all();
118 * This is the lockd kernel thread
123 int err = 0, preverr = 0;
124 struct svc_rqst *rqstp = vrqstp;
126 /* try_to_freeze() is called from svc_recv() */
129 /* Allow SIGKILL to tell lockd to drop all of its locks */
130 allow_signal(SIGKILL);
132 dprintk("NFS locking service started (ver " LOCKD_VERSION ").\n");
135 * FIXME: it would be nice if lockd didn't spend its entire life
136 * running under the BKL. At the very least, it would be good to
137 * have someone clarify what it's intended to protect here. I've
138 * seen some handwavy posts about posix locking needing to be
139 * done under the BKL, but it's far from clear.
144 nlm_timeout = LOCKD_DFLT_TIMEO;
145 nlmsvc_timeout = nlm_timeout * HZ;
150 * The main request loop. We don't terminate until the last
151 * NFS mount or NFS daemon has gone away.
153 while (!kthread_should_stop()) {
154 long timeout = MAX_SCHEDULE_TIMEOUT;
155 RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
157 /* update sv_maxconn if it has changed */
158 rqstp->rq_server->sv_maxconn = nlm_max_connections;
161 flush_signals(current);
166 timeout = nlmsvc_retry_blocked();
169 * Find a socket with data available and call its
172 err = svc_recv(rqstp, timeout);
173 if (err == -EAGAIN || err == -EINTR) {
178 if (err != preverr) {
179 printk(KERN_WARNING "%s: unexpected error "
180 "from svc_recv (%d)\n", __func__, err);
183 schedule_timeout_interruptible(HZ);
188 dprintk("lockd: request from %s\n",
189 svc_print_addr(rqstp, buf, sizeof(buf)));
193 flush_signals(current);
194 cancel_delayed_work_sync(&grace_period_end);
195 locks_end_grace(&lockd_manager);
197 nlmsvc_invalidate_all();
198 nlm_shutdown_hosts();
203 static int create_lockd_listener(struct svc_serv *serv, const char *name,
204 const int family, const unsigned short port)
206 struct svc_xprt *xprt;
208 xprt = svc_find_xprt(serv, name, family, 0);
210 return svc_create_xprt(serv, name, family, port,
216 static int create_lockd_family(struct svc_serv *serv, const int family)
220 err = create_lockd_listener(serv, "udp", family, nlm_udpport);
224 return create_lockd_listener(serv, "tcp", family, nlm_tcpport);
228 * Ensure there are active UDP and TCP listeners for lockd.
230 * Even if we have only TCP NFS mounts and/or TCP NFSDs, some
231 * local services (such as rpc.statd) still require UDP, and
232 * some NFS servers do not yet support NLM over TCP.
234 * Returns zero if all listeners are available; otherwise a
235 * negative errno value is returned.
237 static int make_socks(struct svc_serv *serv)
242 err = create_lockd_family(serv, PF_INET);
246 err = create_lockd_family(serv, PF_INET6);
247 if (err < 0 && err != -EAFNOSUPPORT)
256 "lockd_up: makesock failed, error=%d\n", err);
261 * Bring up the lockd process if it's not already up.
265 struct svc_serv *serv;
268 mutex_lock(&nlmsvc_mutex);
270 * Check whether we're already up and running.
276 * Sanity check: if there's no pid,
277 * we should be the first user ...
281 "lockd_up: no pid, %d users??\n", nlmsvc_users);
284 serv = svc_create(&nlmsvc_program, LOCKD_BUFSIZE, NULL);
286 printk(KERN_WARNING "lockd_up: create service failed\n");
290 error = make_socks(serv);
292 goto destroy_and_out;
295 * Create the kernel thread and wait for it to start.
297 nlmsvc_rqst = svc_prepare_thread(serv, &serv->sv_pools[0]);
298 if (IS_ERR(nlmsvc_rqst)) {
299 error = PTR_ERR(nlmsvc_rqst);
302 "lockd_up: svc_rqst allocation failed, error=%d\n",
304 goto destroy_and_out;
307 svc_sock_update_bufs(serv);
308 serv->sv_maxconn = nlm_max_connections;
310 nlmsvc_task = kthread_run(lockd, nlmsvc_rqst, serv->sv_name);
311 if (IS_ERR(nlmsvc_task)) {
312 error = PTR_ERR(nlmsvc_task);
313 svc_exit_thread(nlmsvc_rqst);
317 "lockd_up: kthread_run failed, error=%d\n", error);
318 goto destroy_and_out;
322 * Note: svc_serv structures have an initial use count of 1,
323 * so we exit through here on both success and failure.
330 mutex_unlock(&nlmsvc_mutex);
333 EXPORT_SYMBOL_GPL(lockd_up);
336 * Decrement the user count and bring down lockd if we're the last.
341 mutex_lock(&nlmsvc_mutex);
346 printk(KERN_ERR "lockd_down: no users! task=%p\n",
352 printk(KERN_ERR "lockd_down: no lockd running.\n");
355 kthread_stop(nlmsvc_task);
356 svc_exit_thread(nlmsvc_rqst);
360 mutex_unlock(&nlmsvc_mutex);
362 EXPORT_SYMBOL_GPL(lockd_down);
367 * Sysctl parameters (same as module parameters, different interface).
370 static ctl_table nlm_sysctls[] = {
372 .procname = "nlm_grace_period",
373 .data = &nlm_grace_period,
374 .maxlen = sizeof(unsigned long),
376 .proc_handler = proc_doulongvec_minmax,
377 .extra1 = (unsigned long *) &nlm_grace_period_min,
378 .extra2 = (unsigned long *) &nlm_grace_period_max,
381 .procname = "nlm_timeout",
382 .data = &nlm_timeout,
383 .maxlen = sizeof(unsigned long),
385 .proc_handler = proc_doulongvec_minmax,
386 .extra1 = (unsigned long *) &nlm_timeout_min,
387 .extra2 = (unsigned long *) &nlm_timeout_max,
390 .procname = "nlm_udpport",
391 .data = &nlm_udpport,
392 .maxlen = sizeof(int),
394 .proc_handler = proc_dointvec_minmax,
395 .extra1 = (int *) &nlm_port_min,
396 .extra2 = (int *) &nlm_port_max,
399 .procname = "nlm_tcpport",
400 .data = &nlm_tcpport,
401 .maxlen = sizeof(int),
403 .proc_handler = proc_dointvec_minmax,
404 .extra1 = (int *) &nlm_port_min,
405 .extra2 = (int *) &nlm_port_max,
408 .procname = "nsm_use_hostnames",
409 .data = &nsm_use_hostnames,
410 .maxlen = sizeof(int),
412 .proc_handler = proc_dointvec,
415 .procname = "nsm_local_state",
416 .data = &nsm_local_state,
417 .maxlen = sizeof(int),
419 .proc_handler = proc_dointvec,
424 static ctl_table nlm_sysctl_dir[] = {
428 .child = nlm_sysctls,
433 static ctl_table nlm_sysctl_root[] = {
437 .child = nlm_sysctl_dir,
442 #endif /* CONFIG_SYSCTL */
445 * Module (and sysfs) parameters.
448 #define param_set_min_max(name, type, which_strtol, min, max) \
449 static int param_set_##name(const char *val, struct kernel_param *kp) \
452 __typeof__(type) num = which_strtol(val, &endp, 0); \
453 if (endp == val || *endp || num < (min) || num > (max)) \
455 *((int *) kp->arg) = num; \
459 static inline int is_callback(u32 proc)
461 return proc == NLMPROC_GRANTED
462 || proc == NLMPROC_GRANTED_MSG
463 || proc == NLMPROC_TEST_RES
464 || proc == NLMPROC_LOCK_RES
465 || proc == NLMPROC_CANCEL_RES
466 || proc == NLMPROC_UNLOCK_RES
467 || proc == NLMPROC_NSM_NOTIFY;
471 static int lockd_authenticate(struct svc_rqst *rqstp)
473 rqstp->rq_client = NULL;
474 switch (rqstp->rq_authop->flavour) {
477 if (rqstp->rq_proc == 0)
479 if (is_callback(rqstp->rq_proc)) {
480 /* Leave it to individual procedures to
481 * call nlmsvc_lookup_host(rqstp)
485 return svc_set_client(rqstp);
491 param_set_min_max(port, int, simple_strtol, 0, 65535)
492 param_set_min_max(grace_period, unsigned long, simple_strtoul,
493 nlm_grace_period_min, nlm_grace_period_max)
494 param_set_min_max(timeout, unsigned long, simple_strtoul,
495 nlm_timeout_min, nlm_timeout_max)
497 MODULE_AUTHOR("Olaf Kirch <okir@monad.swb.de>");
498 MODULE_DESCRIPTION("NFS file locking service version " LOCKD_VERSION ".");
499 MODULE_LICENSE("GPL");
501 module_param_call(nlm_grace_period, param_set_grace_period, param_get_ulong,
502 &nlm_grace_period, 0644);
503 module_param_call(nlm_timeout, param_set_timeout, param_get_ulong,
505 module_param_call(nlm_udpport, param_set_port, param_get_int,
507 module_param_call(nlm_tcpport, param_set_port, param_get_int,
509 module_param(nsm_use_hostnames, bool, 0644);
510 module_param(nlm_max_connections, uint, 0644);
513 * Initialising and terminating the module.
516 static int __init init_nlm(void)
519 nlm_sysctl_table = register_sysctl_table(nlm_sysctl_root);
520 return nlm_sysctl_table ? 0 : -ENOMEM;
526 static void __exit exit_nlm(void)
528 /* FIXME: delete all NLM clients */
529 nlm_shutdown_hosts();
531 unregister_sysctl_table(nlm_sysctl_table);
535 module_init(init_nlm);
536 module_exit(exit_nlm);
539 * Define NLM program and procedures
541 static struct svc_version nlmsvc_version1 = {
544 .vs_proc = nlmsvc_procedures,
545 .vs_xdrsize = NLMSVC_XDRSIZE,
547 static struct svc_version nlmsvc_version3 = {
550 .vs_proc = nlmsvc_procedures,
551 .vs_xdrsize = NLMSVC_XDRSIZE,
553 #ifdef CONFIG_LOCKD_V4
554 static struct svc_version nlmsvc_version4 = {
557 .vs_proc = nlmsvc_procedures4,
558 .vs_xdrsize = NLMSVC_XDRSIZE,
561 static struct svc_version * nlmsvc_version[] = {
562 [1] = &nlmsvc_version1,
563 [3] = &nlmsvc_version3,
564 #ifdef CONFIG_LOCKD_V4
565 [4] = &nlmsvc_version4,
569 static struct svc_stat nlmsvc_stats;
571 #define NLM_NRVERS ARRAY_SIZE(nlmsvc_version)
572 static struct svc_program nlmsvc_program = {
573 .pg_prog = NLM_PROGRAM, /* program number */
574 .pg_nvers = NLM_NRVERS, /* number of entries in nlmsvc_version */
575 .pg_vers = nlmsvc_version, /* version table */
576 .pg_name = "lockd", /* service name */
577 .pg_class = "nfsd", /* share authentication with nfsd */
578 .pg_stats = &nlmsvc_stats, /* stats table */
579 .pg_authenticate = &lockd_authenticate /* export authentication */